Improvement in sewing-mach in es



J. G-. FOLSOM. SEWING MACHINE.

Patented Nov. 29. 1864.

25a/wafer.'

UNITED STATES PATENT OFFICE.

JGHN FOLSOM, OF WINOHENDON, MASSACHUSETTS.

IMPROVEMENT iN'si-:wlNG-MAGHINES;

Sprcilication forming part of Letters Patent No. 45,236, dated Novemberl, 1864.

To all cham it may concern:

` Beit known that I,- JoHN G. FoLsoM', of Vinchendon, in. the county of Worcester and State of Massachusetts, have invented new and useful Improvements in Sewing-Machines; and I do hereby declare thatthe followingis a t'ull, clear, and exact description thereof, which Vwill enable others skilled in the art to make and use the same, reference being had to the accompanying drawings, forming apart ot' this specification, in which- Figure 1 is a plan as seen from below of atable or bed-plate oi' a sewing-machine contain- `7 and 8 are respectively aplan andacross secmethod ot' securing the lower needle or looper to its shaft.

It is necessary in using the sewing-machine in which an upper and lower needle are employed that these needles should in passing each other come so near as to enable the lower needle or looper to enter-the loop of the upper needle without fail, their'paths being in fact so nearly in thesame planethat their sides often come in contact. 'lhis has been found necessary in order to insure the formation ot' the stitch, since, it' the needles were not in close proximity when the one is to take the loop of the other it would be liable to pass outside of the loop on account of the rapid movements ot' the parts, especially when the loop of the'upper thread is imperfectly formed. The needle bar or arm which carries the upper needle is therefore made to travel in acertain tixed path, which will bring the needle in its reciprocations always near enough to the path of the looper, which has always heretofore traveled in a fixed path also. New it is evident that whenever by reason of a changein the character of the work to be sewed the needle has to be replaced by one finer .or coarser its proximity to the path of the lowerneedlewillbe changed by halt' the dii-"terence in the diameter of the needle substituted, which, it tiner than the one for which the machine was originally adjusted, will cause the needles to be too far apart to enable the lower needle always to take the loop of the upper needle, and ifcoarser will cause the needles to crowd each other so that one or both will become bent and made untit' for service, or perhaps broken. The injury.

usu'ally falls upon the upper needle, which is more slender than the looper.

In order to prevent injuries to the needles and delays in the sewing, as well as imperfect` sewing from this cause, it h as for years been customary to make sewing-machine needles of the form shown in Fig. 3, a portiou,f, beingl cut away just above the eye, so that therewill be alwaysa space forthe passage of thclooper between the side ot the needle andthe thread, whatever may be the size of the needle, the portion cut away being of course the greater the coarser the needle. Under this arrangementit is evident that it1 the adjustment of' the needle-bar and of the looper-shaft be made from reference to the finest needle to be used .on the machine, each needle ot' a larger size must be cut away one-half the difference between its diameter and that of the finest' nee.- dle, in order to bring its a'xis near enough to the tixed path of the loo-per. As there are about six sizes of upper needles, it is clear that this mode of ad j ustmentis expensive, laborious, and difficultot'accomplishment. Thecutting away of the needle also weakens it and causes it to break oftentimes, because it is not then strong enough to withstand the force necessary to send it through the cloth, leather, or other material to be sewed.

Another feature of my invention is the mode of securing the looper upon the'end of its shaft so that it cannot be displaced iu working, and cannot be put upon its shaft in afalse position by the most unskillful person.

A lrepresents the bed-plate of an ordinary sewing-machine inverted, and B the loopershaft of a looper, L, for se'wing with a single thread. The shaft is supported in adjustable bearings C, secured to the bed-plate, as usual, in which it is free to slide endwise.

The class ofloopers which I have chosen to illustrate my invention is that which makes the chain-stitch with the needlethread,its motion being vibratory about the axis of its shaft, which usually, as here, is made to rock in its bearin gs sudiciently to gi ve the necessary movements to the looper.

A collar, b, is firmly secured to the shatt B at any suitable point iu' its length. This eollar is slotted in a direction at right angles to its axis to receive a pin, n, loosely fitting in it, fast on a shipper, l), which is secured to the bed-plate by a lulcrum-pin, (t, and by means of a clamping-screw, e. The clamping-screw c passes into a screw-threaded hole tapped in the hed-plate, through a transverse slot or rye, (I, tormed in the shipper, and clamps the shipper in any position to which ithas been moved by means of the handle c.

. The operation of the parts is as follows: When a change is to be made in the size of' the needle from larger tosmaller, or vice versa, the screw cis-turned so as to release the shipper, when the operator seizes the handle eand be proceeded with. One effect ot' this adjustment ot' the looper is to save the necessity of cutting away part of the side ofthe needle, as before explained, and to enable needles of all sizes to be made with straight sides, thereby saving much labor and expense now expended vin cutting them away.

ltisevitleutthat this improvement is equally applicablefto revolving loopers by continuing the slot which receives the pin of the shipper so that it shall encircle the collar b; or the collar b may be composed of two rings fixed to the shaft at such a distance apart as to permit the pin to pass between them.

The looperisscenin detailin Figs. 4, 5,-and (i, with thedevices by which I secureiton its shaft. J is a head, which is shrunk on the looper end ofthe shaft B, or secured by any other means. Itis countersunk, as seen in Fig. 5, and its edge on one side is cnt away at K, seas to receive the 'eye ofthe lcoper iitting in the slot K, so that the. eye of the looper is iiush with the .head J. It is then secured to the head J by a screw, O.y

Instead of making the head J separate and` then uniting it to the shaft, the end of the shaft itself may be countersunk so as to receive the looper. By this means the iooper is xed in l its true position on the shaft without possibility ot mistake, while it can only be put-.out ot position by the torsion of the shat't itself'. The measure of atljustn'lentof the looper-shaft need not be left to the skill of the operator; but it can be ascertained by means of au index on the top ofthe bed-plate, which may bo moved from the shipper through a slot made in the bed-plate, a scale being marked 0n the bedplate to indicate the positions ot' the index for the different sizes of needles usually employed on sewing-machines.

I claim as new and desire to secure by Letters Patent- 1. Adjusting lthe looper or lower needle ofal sewing-machine to suit the different Isizes ot upper needles by an endwise motion ofits shaft, whether it he a vibrating' or revolving looper, substantiallyin the manncrand for thepnrpose above described.

2; Locking the looper in `its proper position by sinking' its eye and shank in the end of its shaft, substantially as above described. 

